This invention relates to an apparatus for subaqueous pile driving at considerable depths comprising a pile driving block, means for lifting and lowering the block from a position above the water line, and means for guiding the block during ascent or descent. Hoses and cables for supplying energy, air, etc. to the submerged pile driver are also provided.
In known devices of this kind the pile driving block is lifted and lowered by hoisting means on board a floating barge or the like via guide means on a stationary underwater platform or tower. The guide means are typically spaced along the framework of the platform and serve to guide the pile and the pile driving means during their lowering.
To supply energy to and control the operation of the pile driving block and to provide air in the region where the ram strikes the head of the pile, hoses and cables are needed which must also be guided from above the water line down to the pile driving block. These hoses and cables present a problem in that they must move from a position above the water line in synchronism with the movement of the hoisting means and with the reciprocating movements resulting from the pile driving operation, and in most cases such hoses and cables are not adapted to take considerable tensile stresses. This deficiency may cause problems when the apparatus for guiding the hoses and cables is disposed on a floating barge or the like which is exposed to wind and wave action. In addition, the cables may become entangled by underwater currents, not only with each other but also with the guiding means, particularly when the latter comprise guide rings disposed along the framework of a stationary submerged platform or tower. Not only the pile and the pile driving block but also the hoses and cables must be guided through such rings.